Choking and blinded by smoke in a Coney Island building elevator as a fire raged Sunday, two NYPD cops frantically radioed for help, screaming, “We can’t breathe!’’ before collapsing unconscious, authorities and sources said.

“Help! Help! We can’t breathe. Get us out of here! We don’t know where we are. We’re in an elevator. We don’t know what floor we’re on. We can’t breathe! We can’t see!” screamed one of the cops over the police radio.

Housing Officer Dennis Guerra, 38, a married dad of four, was in cardiac arrest by the time help arrived.

He was rushed to Coney Island Hospital and then airlifted to Jacobi Hospital in The Bronx, where he remains in critical condition. Both Police Commissioner Bill Bratton and Mayor de Blasio rushed to Jacobi.

Guerra’s partner, Rosa Rodriguez, 36, a mother of four, was transported from Lutheran Hospital in Brooklyn to Cornell Medical Center’s burn unit in Manhattan and placed in a hyperbaric chamber.

An officer is rushed to the hospital.Photo: Theodore Parisienne

Medical personnel respond to the scene.Photo: Theodore Parisienne

She, too, was listed in critical condition.

The partners were on routine patrol at the housing project at 2007 Surf Ave. when they investigated a 911 call of smoke on the 13th floor, officials said.

Residents said someone had intentionally lit a mattress on fire in the hallway.

For some reason, the cops jumped into an elevator.

“You’re never supposed to use the elevator because you might get stuck,’’ the source said.

The cops were immediately engulfed in smoke and heat when the elevator reached the 13th floor.

“Fire Department personnel arrived at the building and made their way up to the 13th floor where they found both officers unconscious and unresponsive on the hallway floor,” said Bratton. “Responding firefighters pulled both officers back into the elevator and brought them downstairs where EMS personnel were waiting.”

A resident who saw the blaze through her apartment peephole said someone had lit a mattress in the hallway, sparking the blaze.

“Housing usually comes in the morning and takes trash down. Today, someone pulled out a mattress from a back stairwell and didn’t bring it down,’’ said 13th-floor resident Yolanda Vargas.

“By the time I looked through my peephole, all I could see was flames,” Vargas said.

“I went to the back window, opened the window and waited for the firefighters to tell us what to do,” she said.

A woman and a young man who appeared to be around 15 were taken from the scene by officers for questioning, sources said.

Bratton and de Blasio both comforted Guerra’s family — including his stricken parents — at his bedside.

“It’s incredibly difficult work these men and women do,” the mayor said. “I say this on behalf of all New Yorkers: Our hearts go out to the families. We will stand by them.”

Three firefighters and nine residents also suffered minor injuries and were treated at the scene and released, Bratton said.